“…18 The Velcro effect can be reduced by an excessively large pocket, an immature periprosthetic capsule, an unstable prosthetic location, a double capsule, the occurrence of a periprosthetic membrane, or excessive intracapsular fluid, which can act as a lubricant. 2,3,19,20 A double capsule is a periprosthetic capsule surrounded by another capsule. 3,19,20 We believe a periprosthetic membrane is the other end of the spectrum.…”